Brush holder



May 31, 1949. E. J. TALAMINI 2,471,591

BRUSH HOLDER Filed Jan. 31, 1945 v INVENTOR. E. J. TALAM/N/ Qt -41L bmjxw fiurwzl.

A TTOPNEV Patented May 31, 1949 BRUSH HOLDER Elio J. Talamini, Kearney, N. J assignor to Joshua Hendy Iron Works, Ampere, N. J a corporation of Nevada Application January 31, 1945, Serial No. 575,390

2 Claims. 1

This invention relates to brush holders for dynamo electric machines and more particularly to a brush holder having resilient means for maintaining the brush in contact with the commutator.

Heretofore brush holders have been provided with an arm engaging the brush which normally retains the brush in engagement with the commutator and in which the brush is held in position by means of a spring permitting the brush to recede in the holder to accommodate itself to irregularities in the surface of the commutator. While such constructions are suitable for use under ordinary conditions, I have found that when the dynamo electric machine is used in places where it is subject to sudden shocks, the spring-pressed arm may permit the brush to be forced from the holder, if the shock is great enough, and fall into the rotating parts of the machine and cause damage.

In the present invention I provide a brush holder together with a spring-pressed arm to hold the brush in engagement with the commutator and I further provide a stop arranged in the path of the arm to normally prevent the arm from moving far enough to allow the brush to escape from the holder. As the brushes must be replaced at intervals, the stop is so constructed that it can be moved out of the path of the arm to permit the arm to move a sufficient distance to remove a brush and insert an other.

The stop preferably comprises a leaf spring member having one end secured to the body of the holder and having its intermediate portion arranged in the path of the spring-pressed arm to be engaged by the arm and thus limit its movement. The other end of the stop bears against the body of the holder to normally retain the stop in an operative position. When a brush is to be replaced, the intermediate portion of the stop is compressed to bring it out of the path of the spring-pressed arm. The arm may then be moved against the tension of the spring to permit removal of the brush from the holder and the substitution of a new brush,

In the accompanying drawing I have shown one embodiment of the invention.

In this showing:

Fig. 1 is a side elevation, parts being shown in section;

Fig. 2 is a front view; and

Fig. 3 is a detailed, front and side elevation of the stop.

Referring to the drawing, the reference numeral I designates generally the body of the holder. The body may be formed of any desirable size and shape and may be cast or otherwise fabricated. It is substantially rectangular in horizontal cross section consisting of side walls 2, a rear wall 3 and a front wall 4. The rear wall is provided with threaded openings 5 for the reception of bolts or other securing means to mount the brush holder on the frame of the machine in proper position to dispose the brush at the desired point adjacent the commutator 6.

A brush 1, preferably formed of carbon, is received in a holder 8 mounted on the front of the body I. The holder consists of a piece of metal shaped to provide a pair of side walls 9 and a front wall In parallel to the front wall 4 of the body. The side walls extend over the side walls of the body and are secured thereto by rivets II or other suitable fastening means. The walls 9 and I 0 cooperate with the front wall 4 of the body to fairly snugly receive the brush 1.

A spring-pressed arm I2 is adapted to engage the upper surface of the brush to retain it in engagement with the commutator 6. As shown, this arm is carried by a pin or shaft I3 rotatably mounted in ears I4 formed on the side walls of the body. Adjacent the pivot the arm I2 is provided with an enlargement I5 in the form of a segment of a circle and the outer edge of this segment is provided with a plurality of notches I6.

Arm I2 is caused to exert pressure on the brush by means of a spring designated generally by the reference numeral II. The ends I8 of this spring engage the upper surface of the holder and a portion I9 of the spring adjacent each end is coiled around the shaft I3. The central portion of the spring forms a loop 2|] which extends outwardly and one side of the loop is received in one of the notches [6 as shown to apply the desired force to the arm. This force may be adjusted by changing the position of the loop 20 from one to another of the notches It or the loop may be arranged in engagement with the top of the arm I2.

To prevent the brush from being forced out of the holder in case of sudden shock great enough to completely overcome the force of the spring I1, I provide a stop 2| arranged in the path of the segmental portion I5 of the arm I2. As shown, the stop comprises a leaf spring member having one end portion 22 secured to the body of the holder by rivets 23 or other suitable fastening means, Beyond the end portion the stop is extended at an incline as at 24 and is then bent or curved as at 25 to provide the engaging portion. Beyond the portion 25 the stop member is provided with a loop 20 and the end portion 2'! engages the face of the rear wall 3 of the body of the holder to retain the stop member in position to be engaged by the se ment l5 as shown in Fig. 1 of the drawing.

The operation of the device will be apparent from the foregoing description. When a brush is to be placed in the holder the stop is grasped along the portion 215 and pressure applied to bring it out of alignment with the segment E5 to permit the arm I2 to be rotated in a clockwise direction on the pin or rivet It whereby a brush may be removed from the holder and replaced by a new one. In normal operation the loop 20 of the spring is arranged in one of the'notchesifi or on the upper surface of the arm E2 to apply the proper spring tension to the brush. The dottedline position of the end of the arm 52, shown in Fig. .1 of the drawing, indicates the position of the arm when tension is applied to it by placing the loop portion of the spring in one of the notches of thesegment. With the parts in the position shown in Fig. 1 of the drawing, if the dynamo electric machine issubmitted to extreme shock, such as when a torpedo hits a ship on which the dynamo electric machine is installed, the brush will move upwardly in the holder against the tension of the spring it. This upward movement, however, is limited by the stop 2!. The arm l2 can only move as far as the full line position shown in 1 of the drawing, and the brush is thus prevented from jumping out of the holder. To insert a new brush when necessary, the stop is. merely moved out of the path of the segment byapplying enough force to it to compress the portions 2 2- and .27 toward each .other, and the arm moved upwardly a sufficient distance to permit the brush to bezremoved.

I claim:

1. A brush holder comprising a body portion, a brush receiving portion mounted on the body portion, an arm pivotally mounted on the body portion andengaging the brush to hold it in position, a spring for applying tension to said arm, and a stop comprising a leaf spring member mounted on the body portion of the holder and arranged in the path of the arm to limit its movement in a direction away from the brush, the stop being normally positioned to prevent movement of the arm a distance sufiicient to permit removal of the brush from the holder.

2. A brush holder comprising a body portion, a brush receiving portion mounted on the body portion, a pin mounted on the body portion, an arm rotatably mounted on the pin, one end of the arm being adapted to engage a brush in the holder to retain it in position, a spring surroundingthe pin and engaging the arm to apply tension to the brush, and a stop comprising a leaf spring member mounted on the body portion of the holder and arranged in the path of the arm to limit its movement in a direction away from the brush, the stop being normally positioned to prevent movement of the arm a distance sufficient to permit removal of the brush from the holder, the stop being capable of being moved to an inoperative position to permit further movement of the arm to enable the brush to be removed from the holder.

ELIO J. TALAMINI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 779,814 Staver Jan; 10, 1905 882,565 Howell Mar. 24, 1908 1,569,367 Hartman Jan. 12, 1926 FOREIGN PATENTS Number Country Date 25,990 Great Britain 1903 9,373 Great Britain 1904 42,470 Austria June 10, 1910 353,544 Great Britain July 30,1931 

